Organic phosphorus abietates and process of manufacture



Patented June 12, 1945 L ORGANIC PHOSPHORUS ABIETATES AND PBJQCESS OFMANUFACTUB Ernest F. Engelke, Merchantville, N. J., assignor to'CitiesService Oil Company, New York, N. Y., a corporation of Pennsylvania.

No Drawing.

Original application January 8, 1942, Serial No. 425,965.

Divided and this application December 15, 1942, Serial No. 469,126

6 Claims.

This invention relates to the manufacture of improved organic phosphoruscompounds. More particularly the invention relates to improvedphosphorus organic compounds made from the esters of abietic acid. Thisapplication is a division of pending application Serial No. 425,965,filed January 8th, 1942.

Many of the esters of abietic acid are commercial products as shown bythe fact that Patent No. 2,217,764 has been granted to Morway for theiruse in the manufacture of sulfurized materials to be used in cuttingoils and in lubricants generally.

The primary object of the present invention is to provide improvedphosphorus derivatives of the esters of abietic acid.

Another object of the invention is to provide an improved process of themanufacture of phosphorus abietates.

With these objects in view, the present invention includes improvedphosphorized abietic esters or phosphorus esters containing an organicabietic acid ester as a substituent. In general, the compoundscontaining phosphorus may be made by chlorinating the abietate andreacting the chlorinated product with a phosphorus chloride in thepresence of a Wurtz- Fittig catalyst such as sodium.

The phosphorus derivatives produced preferably contain one or moreabietate groups attached to phosphorus by a phosphorus-carbon linkage.In carrying out the Wurtz-Fittig reaction, the initial organicphosphorus compounds used for reacting with the abietate may berepresented by the general formula (ROhPCl, (RO)PCl-.-, (RO)2PSC1, and(RO)PSCh, in which R is an alkyl or aromatic group preferably phenyl orcresyi. If the abietic acid esters are represented generally by R', thechlorinated esters will have the general formula R'Cl, while the finalproducts may be represented by the general formula (ROMPR', (RO)PR'2,(ROMPSR' and (ROlPSR/z, in which each R is directly attached tophosphorus.

The method of manufacturing the improved phosphorus abietate esters andtheir effectiveness, for example as film strength agents, can

be illustrated by reference to the following specific examples:

Example No. 1

According to a preferred form of the invention, a phosphite estercontaining two phenol groups and a methyl abietate group is prepared bythe following procedure:

The methyl abietate is first chlorinated by direct contact with chlorineat a temperature of about 180 C. until sufiicient chlorine has beenadded to correspond to about one atom of chlorine for each molecule ofmethyl abietate. After the chlorination reaction the resulting productwas diluted with two volumes of xylol and shaken with sufiicient solidslaked lime to neutralize the product, after which it was filtered. Theresulting chlorinated methyl abietate showed a chlorine content of11.88%.

The primary reaction was carried out by first placing about twenty partsby weight of metallic sodium in 105 parts of xylol which is used as asolvent, and subjecting it to reflux heating with intense agitation, theheating being eflected by means of an oil bath maintained at atemperature of about320 F., so that the sodium and xylol are heated to atemperature of from 260 to 270 F. thereby effecting melting and intimatedispersion of the sodium. After the dispersion of the sodium in thexylol in extremely fine particles, 9. mixture of 250 parts by weight ofdiphenyl phosphorous acid chloride and 350 parts of chlorinated methylabietate dissolved in about 250 parts of xylol was slowly added to thehot sodium dispersion while continuing the agitation and maintaining thetemperatures. Upon completing the introduction of these materials, thetemperature of the mixture was maintained at from about 270 to 280 F.for a period of several hours.

The resulting reaction mixture was filtered hot for the separation ofthe sodium chloride, the filter cake being washed twice with hot xylol.An additional but relatively small quantity of filtrate was obtained bydigesting the filter cake with water which dissolved the sodiumchloride. The resulting combined filtrate in xylol solution was alkalinebut was made slightly acidic with hydrochloric acid and then washed withwater until neutral. The resulting purified neutral product wasseparated from the xylol by steam distilling the latter finally at'areduced pressure of about mm. of Hg. The finished product was a veryviscous liquid of wine-red color in transmitted light and iaint greenishdark color in reflected light. It contained 2.95% of phosphorus and wasfound to be readily soluble to the extent of 10% to 15% in motor oils.

The effectiveness of the product as a film strength agent in lubricatingoils is illustrated by the fact that blends of 0.5, 1.0 and 1.5%dissolved in a Pennsylvania lubricating oil of 20 SAE number showedload-carrying capacities on 35,800 lbs. per square inch respectively..The load-carrying capacity of the Pennsylvania lubricating oil alone wasonly 14,100 lbs. per square inch. The motor oil blends were tested forwear and corrosion with various bearing metals such as Cd-Ag-Cu-steel,Cu-Pb-steel, babbit, etc. All bearings were bright, smooth, shiny anduntarnished.

Example No.2

A phosphite ester containing two cresyl groups and one methyl abietategroup was made by the same procedure used above in Example No. 1. Thiproduct was also liquid and had about the same color characteristics asthe product of Example No. 1, and contained 3.92% of phosphorus. It wasblended in a SAE Pennsylvania lubricating oil in the proportions of 0.5,1.0 and 1.5 percentages, and the resulting blends tested on the Timkentesting machine. The load-carrying capacities of these blends wererespectively 30,500, 31,600 and 33,900 lbs. per square inch, whereas theparticular lubricating oil alone carried only 15,150 lbs. per squareinch.

Example N0. 3

A thiophosphate ester was prepared by the procedure used in Example No.1 by reacting dicresyl thiophosphoric acid chloride with chlorinatedmethyl abietate. The resulting product contained 3.88% of phosphorus,was a liquid, and had about the same color characteristics as theproduct of Example No. 1. Blends were made with a 20 SAE Pennsylvanialubricating oil stock containing 0.5, 1.0 and 1.5% of the thiophosphateester. These blends showed load-carrying capacities on the Timkentesting machine of 16,750,

29,000 and 30,500 lbs. per square inch respectively; while the oil alonecarried only 15,150 lbs. per square inch.

The blends in this instance, as also in Example No. 2, werenon-corrosive to the bearing metals referred to above, all of whichremained smooth, shin and bright.

Example No. 4

Chlorinated methyl dihydroabietate (10.58% Cl) was reacted with adiphenol phosphorous monochloride (C6H50)2PC1, under the conditionsdescribed in Example No. 1 to produce a product containing 4.30% ofphosphorus and which had substantially the color characteristics of theproduct described in Example No. 1. Portions of the product were blendedwith a 20 SAE Pennsylvania lubricating oil stock in the proportions of0.5, 1.0 and 1.5% and the blends showed loadcarrying capacities on theTimken testing machine of 25,800, 29,400 and 31,500 lbs per square inch,respectively. The oil alone had a loadcarrying capacity of 15,750 lbs.per square inch. In the bearing tests, the blends were non-corrosive andleft the bearings smooth and bright with only a slight tarnish.

Example No. '5

Monocresyl phosphorous dichloride,

CH3.CsI-It.O-PC12 was reacted with chlorinated methyl dihydroabietate(10.58% Cl) under the conditions described in Example No. 1, to producea phosphite believed to contain two of the abietate groups. Theresulting product contained 2.47% of phosphorus and had the generalcharacteristics of the product produced in Example No. 1, except theTimken testing machine of 27,400, 30,400 and that it was more viscous.The structure or the product is believed to be represented by thegeneral formula (RO)PR2.

The effectiveness of this material as an extreme pressure agent isillustrated by the fact that blends of 20 SAE Pennsylvania lubricatingoil containing 0.5, 1.0, and 1.5% of the product showed load-carryingcapacities on the Timken testing machine of 31,400, 29,900 and 27,300lbs. per square inch respectively; whereas, the oil alone showed aload-carrying capacity of only 16,550 lbs. per square inch. The tests ofthe blends on hearing metals showed very low losses. and most bearingsremained shiny, smooth and bright, although the Cu-Pb-steel bearingshowed a slight tarnish.

In addition to the abietates used in the foregoing examples, otheresters may be employed in the manufacture of the improved compounds suchas ethyl, propyl, butyl, amyl and other esters of either-abietic acid orthe dihydro compound. Aromatic esters may also be used as those ofphenol, cresol, benzyl alcohol and the naphthols. Furthermore, theesters mentioned by Van Antwerpen in his article in the News Edition" ofthe American Chemical Society for November 25, 1941, pages 1255, 1256and 1258,

may be employed. This article gives the properties of the methyl estersused in the foregoing examples. The esterification of abietic acid andthe production of dihydroabietates results in compounds havingpronounced differences from the original acid.

While it is believed that the reactions described above in connectionwith the examples, produce the compounds indicated, it may be that someproportions of other products are produced as for example by thecombination of two molecules of the chlorinated abietate or thecombination of two of the phosphite groups by a P-P linkage.

While metallic sodium is preferred in the Wurtz-Fittig reactions, it isbelieved that substantially the same results are obtainable by the useof lithium, potassium, finely divided silver, copper and zinc, thesemetals being of known utility in carrying out certain Wurtz-Fittigsynthesis. Likewise, the abietate may be halogenated by other halogensthan chlorine, particularly iodine and bromine,

While the invention has been described in connection with themanufacture of phosphites and thiophosphates, the simple phosphatederivatives may be made where the presence of sulphur is foundundesirable. These phosphates may be produced by oxidizing the finishedphosphite or by starting with (R0) 2POC1 or (RO)POC12. The resultingcompounds will have the general formula (ROJzPOR' and (RO)POR2 and RaPO,the R being connected directly to phosphorus with a P-C linkage. Thephosphates therefore will have the general formula (RO)2PXR' and (R0)PXR2, in which X is sulfur or oxygen.

The R substitute in the foregoing examples has been either phenyl orcresyl, but may represent any suitable aromatic hydrocarbon or aliphatichydrocarbon radical, the latter preferably consisting of from four toseven carbon atoms. Any of these substituents may be halogenated.

While the foregoing invention has been described and illustrated inconnection with the use of the improved compounds as addition agents forlubricating oils, it is to be understood that the invention contemplatestheir use for other purposes for which they are adapted, as for example,in making cutting diagnoses and flushing oils. Furthermore, the improvedcompounds may be used as addition agents for other oils such as fattyoils, synthetic oils and esters, since they are non-corrosive and resistheat, light and oxidation.

Having thus described the invention in its preferred form, what isclaimed as new is:

1. A cresol ester of phosphorus containing an abietate substituentdirectly attached to the phosphorus of the ester with P-C linkage.

2. A phosphorus compound having the general formula (ROlzPR' wherein Rrepresents a radical selected from the group consisting of alkylradicals containing from 4 to 7 carbon atoms and aryl radicalscontaining a single phenyl ring, and R represents an abietate directlyattached to phosphorus with aP-C linkage.

3. A composition of matter comprising a Wurtz- Fittig reaction productof a halogenated abietate and a phosphorus halide having at least one R-group attached to phosphorus in which R represents a radical selectedfrom the group consisting of alkyl radicals containing from 4 to 7carbon atoms and aryl radicals containing a single phenyl ring.

4. The process of manufacturing organic phosphorus compounds, whichcomprises reacting a mixture of a halogenated abietate and a phosphorushalide-having at least one Ro-group attached to phosphorus in which R.represents a radical selected from the group consisting of alkylradicals containing from 4 to 7 carbon atoms and aryl radicalscontaining a single phenyl ring, carrying out the reaction in thepresence of sodium at a temperature of from 250 F. to 300 F., and

separating the resulting phosphorus compound from the resulting sodiumhalide.

5. The process of manufacturing organic phosphorus compounds containingan allwl abietate directly attached to phosphorus, which comprisesdissolving in a mutual solvent a halogenated alkyl abietate and aphosphorus halide having at least one RO-group attached to phosphorus inwhich R represents a radical selected from the group consisting of alkylradicals containing from 4 to '7 carbon atoms and aryl radicalscontaining a single phenyl ring, heating the resulting solution to atemperature of approximately 270 F., slowly mingling the solution withsodium until an excess of sodium has been mixed with the solution forthe removal of the halide from the phosphorus halide and the halogenatedabietate, separating the resulting sodium halide, neutralizing theremainder of the reaction mixture with acid, removing the solvent, and'recovering the phosphorus compound.

6. A phenol ester of phosphorus containing an abietate substituentdirectly attached to the phosphorus of the ester with a P-C linkage.

ERNEST F. ENGELKE.

